How often should engine oil be changed at the longest interval?
3 Answers
Engine oil should be changed at intervals between 5,000-10,000 kilometers or every six months to a year. Below is an introduction to the functions of engine oil: 1. Engine oil, also known as engine lubricant, serves to lubricate and reduce friction in the engine, assist in cooling, seal against leaks, prevent rust and corrosion, and provide shock absorption. 2. Changing the oil on time not only extends the engine's lifespan but also effectively reduces the vehicle's fuel consumption. Additional information: If engine oil is not changed for a long time, as its lifespan deteriorates, its lubrication capability rapidly declines, preventing the engine from receiving proper lubrication and leading to abnormal wear. Meanwhile, metal particles cleaned out by the oil, unable to be expelled, accumulate inside the engine, generating large amounts of sludge from the dirt. The engine may also experience increased fuel consumption, reduced power, difficulty starting, abnormal vibrations, and poor operation.
Having repaired cars for many years and seen all kinds of engine issues, I can tell you that oil change intervals should never be generalized—it depends on the specific vehicle condition. If you drive a regular family car mostly for city commuting, full synthetic oil should be changed at most every 10,000 kilometers or 12 months. If you do more long-distance highway driving, you can extend the interval slightly. Never rely solely on mileage; over time, oil naturally degrades, becoming thinner and ineffective. I recommend checking the dipstick before each oil change—if the oil level is low or the color turns black, be alert—this could indicate oil burning or contamination. For daily driving with frequent short trips and stop-and-go traffic, oil oxidizes faster, so it's best to change it every six months to prevent engine carbon buildup and increased wear. Remember, saving a little money now might cost you major repair expenses later!
As an average car owner, I remember once delaying an oil change for a full year, which resulted in increased engine noise and a spike in fuel consumption. The lesson learned is that regular oil changes are crucial. My current practice is to change synthetic oil every 8,000-10,000 kilometers or every 10 months, without waiting for the manual's upper limit. If you frequently drive in city traffic with constant stop-and-go, the oil temperature rises quickly, leading to faster degradation—I'd rather change it a bit earlier. To save money, choosing higher-quality synthetic oil can extend intervals and reduce costs, but don’t cut corners with cheap, low-quality oil. Regularly observe your car, listen for smooth engine sounds at startup, as it helps assess oil condition. In short, combine the manual’s recommendations with your driving habits—don’t cut corners. Protecting your engine means protecting your wallet.
